1. Technical Field
The present invention relates to a removable and sealable cover for machinery compartments containing lubricants and more particularly to a removable and sealable valve cover for the cylinder head of an internal combustion engine.
2. Background Art
Removable covers for machinery compartments enclosing moving lubricated parts are quite common. These covers are usually flanged and sealed by a soft gasket of suitable composition and secured in place by a series of bolts or other fasteners. Removal of the cover usually requires removal of the fasteners and often replacement of the gasket, which may be damaged by the operation. U.S. Pat. Nos. 2,724,378 and 3,396,712 disclose similar removable and sealable covers for an internal combustion engine cylinder head which differ principally in the method of sealing the cover.
U.S. Pat. No. 2,724,378, provides a valve cover with a removable top for safety reasons. The removable top is designed to automatically open to relieve high gas pressures resulting from explosions of unburned fuel which has leaked from between the valve stem and valve guides into the valve chamber. U.S. Pat. No. 3,396,712, provides an oil seal arrangement to prevent leakage between the cover and the valve cover housing.
Each of the above inventions describe a relatively complicated system consisting of many parts including pins, springs, hinges, rivets and seals which are familiar to those skilled in the art and which possess potential points of failure. The other patents are representative of what is in the prior art. Because these systems vary in construction from each other it is difficult to evaluate their effectiveness. Although it may be assumed that they function in the alleged manner, it is reasonable to assume that there is a continuing need for improvement in such removable and sealable covers. Through detailed analysis and testing it appears that the present invention contributes substantially to such needed improvements, particularly for removability, sealability and reliability.
A particular problem with each of these designs is that they are not suitable for use in automotive or power boat racing applications. In drag racing or stock car racing applications, it is not uncommon to stress the engine parts to the extent that the cylinder valves need readjusting after each and every engine run or race. The same is true with power boat racing. As a result, race mechanics will oftentimes remove cylinder head valve covers several times during the course of a single day of racing. The reason for removing the cylinder head valve covers is to gain access to the valve adjusting mechanisms linkage, be it push rod and rocker arm assemblies or overhead cam shafts, in order to adjust the valve clearances.
When the standard cylinder head valve cover is removed, a certain quantity of oil trapped on top of the cylinder head is lost, and usually spilled onto other engine parts including hot exhaust manifolds. Additionally, the valve cover gaskets normally require replacement each time the cylinder head valve cover is removed. This results in added effort, expense, and oftentimes a smokey, oily mess on the engine.
The removable covers of U.S. Pat. Nos. 2,724,378 and 3,396,712, solve the problem of the loss of oil, however, both designs do not provide for adequate lateral access to the valve adjustment linkage to adjust the valves.
The valve adjusting mechanisms are of two general types, the first is a rocker arm and push rod assembly, and the second is an overhead cam. In both cases, current engine designs provide for very compact valve covers which have to be removed more or less vertically up from the cylinder head to clear the valve adjusting mechanism. As a result, the designs of U.S. Pat. Nos. 2,724,378 and 3,396,712 cannot be modified by lowering the cylinder head housing and extending the height of the top cap to allow for lateral access to the valve adjusting mechanisms. The design of the hinges on said patents is such that the top caps would not clear the valve adjusting mechanism when a person attempted to open the cover. The hinging mechanism must be such that the top cap can be removed more or less vertically prior to being pivoted out of the way.
What is needed is a quick release cylinder head valve cover which, when open, will still not spill or allow the loss of oil, yet, will still allow sufficient lateral access to the valve adjusting mechanisms of the engine.